1. Field of the Invention
The present invention relates to a method of sucking vapor of organic solvent employed in, for example, a cleaning device in various industries, as well as an apparatus for recovering the solvent from the vapor. In this invention, the word "vapor" means either misty gas or vaporous gas.
2. Description of the Prior Art
A conventional apparatus of the above-described type is generally constructed in the manner shown in FIG. 9. In FIG. 9, a container 101, which may be a cleaning tank, contains solvent 102. A work inlet 103 and a work outlet 104 are provided to the container 101. A cover 105 is formed at an upper portion of the container 101. A suction pipe 106 is provided to the cover 105 at an opening 107 in the cover 105. Reference numeral 108 denotes a suction device. Reference numeral 109 denotes a recovering device of the solvent 102 which employs activated carbon. Reference numeral 110 denotes vapor of the solvent 102 mixed with air. A work piece or an object to be cleaned which is not shown is inserted from the inlet 103 into the solvent 102, cleaned with the solvent 102 and then taken out through the outlet 104, during which the suction device 108 is operated to suck the vapor 110 of the solvent 102 mixed with air through the opening 107 and the suction pipe 106. The gas 110, which has been sucked together with air flowed in through the inlet 103 and the outlet 104, is sent to the recovering device 109, then the solvent 102 is recovered from the vapor 110.
The above-described conventional apparatus has the following disadvantages.
The recovering device 109 must be built quite large in size because the apparatus requires a large quantity of activated carbon to concentrate the vapor 110 which contains quite a low density of solvent gas. Therefore, the suction device 108 consumes a large amount of power for sucking a large quantity of vapor.
Further, quality of recovered solvent may be deteriorated, e.g., the recovered solvent may be oxidized and the composition of a stabilizer added to the solvent may be imbalanced in the process of said recovering. This will lead to deterioration of quality of the activated carbon.
Therefore, conventional apparatus is expensive.